Device for actuating brake cables or like members for transmitting motions



May 29, 1951 H. w. TREVASKIS 2,555,207 DEVICES FOR ACTUATING BRAKE CABLES OR LIKE MEMBERS FOR TRANSMITTING MOTIONS Filed Oct. 16, 1948 3 Sheets-Sheet l /NVENIOR w? mum Filed Oct. 16, 1948 W. TREVASKIS H. DEVICES FOR ACTUATING BRAKE CABLES 0R LIKE MEMBERS FOR TRANSMITTING MOTIONS 3 Sheets-Sheet 2 May 29, 1951 H. w. TREVASKIS 2,555,207 DEVICES FOR ACTUATING BRAKE CABLES 0R LIKE MEMBERS FOR TRANSMITTING MOTIONS Filed Oct. 16, 194

Patented May 29, 1951 ITEVIGE FOR AGTUA'TING- BRAKE OR'VLIKE MEMBERS FOR TRANSMITTING MOTIONS Henry William Trevaskis, siil'i uu; England,

Signor to- Dunlop Rubber Company- Limited;

London England; a British company Application oe gis, 194.8, SerialNo. 54,942 In Great-Britain November 1, 1947 I This invention relates to" devicesioractu tihg brake cables or like members for transmitting motion. Moreparticulafly the invention relatestosuch a device to be atta hed tot'he control column of an aeroplane and to actuate a cable connected to landing wheel brakes tion thereof. g

Due to space in the aeroplane cabin orcc'ickpit being confined it is desirable that hand lever devices, whilst being readuy accessible t6 the pilot; should not project from their supports suffieiently to obstruct his movement's.

An object of the invention is to provide a device which is of compact construction and when attached to a support does not project unduly therefrom. 7

According to the present invention a device for actuating a brake came or" like Iheihber for transmitting motion comprises a hand lever and a support therefor n which one end of the handlev'er is constrained'tb move ale g'a straight line and a part of the lever intermediate its ends is constrained to move over a predetermined path whereby the said hand l ver is angularly movable relativeto' said support;

Preferably the said support is a plate with a straight slot therein and a camformation on its periphery and the hand lever carriesinter mediate its endsa roller for engagement with the cam formation; one of theends of the 1ev'er' being formed with a pivot slidable inthe $101; (if

the plate and being adapted to be connected t6 tli Cable.

Inone' embodiment oi the invention the device comprises the plate member anda lever having a handleportion and a bifurcated portion-which straddles the plate; in this construction the-- roller for engagement with the cam surfacei's mounted between the bifurcations near their junction with" the handle portion and a second roller is mounted between the ends of the two bifurcations and is disposed within the slot of the plate member; this roller constituting the slidable pivot and the'slotvin which it is acc ')m-' The shape of the second slot and the shape of' the cam: surface are such that when" the brake ever is movedto apply the brakes,,or to release in opera-' 7 3 claims; (Cl. 74'489) 1 attached cause-constructed to which" the rigid them the one roller ihoves over the catfi surface and other-renter moves along the siotih the plate:

The device of the invention is suitame for 1 attachment to a co'ritrbl column such as thatof an aeroplane or the brake handle of motor vehicle. The device should be mounted so that the straight line path ifiwhich the one end of the hand lever is constrained to mbve' is parallel to the axis of the column. Ih stm e cases th device may be termed" with a' band clip attached to the support by which the device can be attached to the cdntiol comm-n. Alternatively the cdhtrol column to which the deviceis to be with'bore'd lugs and the rigid member'with a series (if Holes Capable of be ng brought into register with the bored lugs; the de'vicecan then hefixed' to the control collu'mn means of bultsipassihg through the ho es.

Afurthermodiiication, applicable-iii the case of an aeroplane, is tdfdrih' the grip of the" centrol column separately front the remainder of the control column with suitably dispose-d lugs; member of the hand lever devieis attachedas deser'i edaheve. The'dev'ic'e will then be-a-ttached to the grip of the control column which- Willin tuin beafiiXed to the" main ortion of the central column. In any of these" forms of this-invention which the device is" fixed to a handle or eehtroieeiumnand the'rig'id memher'is' iii the term or a plate, the edge (If the plate is substantially straight, and" is fixed the centrol so that-it i ies in the iahe containing the axis of the handle with the straight edgeagainst the handle or controlcolumn with thehand 1ever: extending upwardly in a position such: that the grip of: the control column or handle and the hand lever can be gripped; simultanenusly. In such an arrange ment the cam? formation will be onthe upper edge ofltheplate andtthe-slot in which the pivet of the lever moveswil l' extendirom adjacent the lower face oi the plate: upwardly to a point below'the top edge of the plate.

Preferably the device according to the inv'en tion also mcorpdr'atesi a: means for retaining the" handllever: in alpha-selected position, tel example in-ap'osition wheretlierbrakes car'rbe maintain d fully applied, without. gripping" the lever. result may be obtained by providing alu'g ro: jectingt fr'om' one face or the lever in a set screw is mounted withv its"; axis parallel to? the. slot l which the toner intermediate the" endsof thef'lever is located-and adetentiuevabiy plane.

mounted in a seating integral with the rigid member so that it can be moved to one position clear of the set screw, thus permitting the brake to be applied or released partially or completely asdesired, or to a second position where the detentflies across the path of the set screw so that when the hand lever is released'the set screw bears against the detent and thus prevents the brakes from being released. Adjustment of the pre-selected position can be made by adjusting the position of the set screw. Instead of making the mounting of the detent integral with the device the detent mounting may form part of the control column, or other supporting member to which the device is attached.

The invention will be further described with reference to the accompanying drawings showing a device for actuating a brake cable in position on the handle of a control column of an aero- In these drawings- Fig. 1 is a cross-section of the device attached to a control column showing the cam plate, the brake being in the off position.

Fig. 2 is a side view of the device shown in Fig. 1 the brake being in the off position.

Fig. 3 is a side view of the device as seen from the side opposite to that depicted in Fig. 2, the brake being in the off position.

Fig. 4 is a cross-section on an enlarged scale taken on the line AA of Fig. 3 with the hand lever in the parking position.

In these drawings the control column handle I (see Figures 1 and 2) is formed on one side with a protuberant portion having a slot extending parallel to the axis ofthe column, in which slot a plate 2 is fixed by bolts 21, the sides of the plate extending axially of the column. A slot 3 is formed from side to side in the plate 2; the slot is open at the lower end and extends upwards approximately parallel with the axis of the control column for rather more than half the height of the plate 2., A second slot 4 is provided in the upper part of the plate 2 and is closed at both ends, this slot being substantially straight but inclined to the axis of the control column. The upper edge of the plate 2 is shaped to form a stop 5 where it meets the outer edge and a cam surface 6 extending towards the grip of the control column. Lever I has an upper slightly bowed handle portion and a lower end portion which is centrally grooved from the lower end upwards to form two sides plates 8-8 disposed one on each side of the plate 2. The lever thus straddles the plate '2. It is retained in position on the plate 2 by a pin 9 passing through the slot 4 and having its ends in the side plates 8-8. In the slot 3 is a roller l0 mounted by ball bearings on a pin l3 disposed transversely of the axis of the control column and supported by the said plates 8, 8, and also mounted on the same pin is a yoke-piece 29 which straddles the roller l0 and is secured to a cable ll connected to the wheel brake mechanism. Another roller or cam follower I2 is similarly mounted on a pin 28 between the side plates 8-8 parallel with the roller l0 and the said roller I2 is in contact with the cam surface 6 of the plate 2. The pins [3 and 28 have a head at one end and the heads abut against the outer face of one side plate 8 while the other end of each pin has a circular groove, the grooves being both engaged by a substantially U-shaped spring clip M which lies against the outer face of the other side plate 8 and retains the pins in position.

When the lever I is in the off position as shown in Figures 1, 2, and 3, the roller 12 is against stop 5, roller I0 is at the lower end of slot 3, and the pin 9 is at the lower end of the slot 4. As thebrakes are applied by moving the handle portion of brake lever 1 towards. the grip of the control column the movement of the lever is constrained by pin 9 to cause the roller [2 to move along the cam surface 6 and the roller it] to move upwards in slot 3. The co-operation of the cam surface 6 and the roller l2 causes the end of the lever connected to the cable to move in a direction parallel to the slot 3 and substantially axially of the cable ll thus exerting a pull thereon.

Integral with the lever 1 and projecting from the outer face of one side plate 8 is a lug l6 (see Fig. 4) formed with a screw-threaded hole, the axis of which is approximately parallel with the axis of the control column and said hole is engaged by a set-screw H which projects at both ends beyond the lug and at one end has a screwdriver slot 18. The set-screw is formed in its periphery with eight longitudinally extending slots [9 adapted to be separately snap-engaged by a bowed clicker spring (not shown) retained in a slot formed in the lug.

Disposed adjacent the outer side of the lug I6 is a rotatable member formed with a circular disc portion 20 (see Figures 3 and 4) the axis of which is parallel with the axis of the rollers 10 and I2; said disc portion is mounted ina bearing boss 2| rigid with the protuberance of. the control column and is retained in the bearing boss by a ball race 22 located in complementary grooves in bearing boss 2| and disc portion 20. A knob 23 is formed on the face of the disc remote from the set-screw l1 and a detent '24 projects from the other face of the disc adjacent its periphery for a purpose described subsequently. Two depressions 25 formed in the bearing boss 2| are angularly spaced apart relatively to the axis of the member 20 and a spring-loaded ball 26 is carried by said knob 23 to co-operate with the depressions.

With the lever 1 in the normal off position, the detent 24 is clear of the screw l'l permitting the brake lever to be applied and released as desired. If, however, while the brake lever is depressed so that the brakes are fully on, the knob 23 is moved from theposition shown in Figure 3 until the spring-loaded ball 26 enters the other depression25, the detent 24 is brought beneath the end of screw 11. Only a partial, release of the brake lever 1 is then possiblethe extent depending upon the position of screw l1 relative to the lug 16. The screw 11 is normally adjusted by means of the screwdriver slot l8 so. that when it abuts against the detent 2'4,v the: brakes are in their parking position. V 1' In using the brake device, assuming thatit is; in the off position with the knob 23 thus in thei position shown in Figure 3, the brakes are .ap-' plied when desired by gripping the grip of the. control column I and the lever I so that the latter is moved towards the control column; the pin 9 then moves along the slot 4 to the upper end thereof and the brakes are applied as has been described above. During this movement the end of the screw I'I visible in Figure 3 moves upwards to the position shown in Figure 4 in which its lower end is above the axis of the circular disc 20, and thus above the position which the detent 24 will assume when the knob 23 is moved to the position shown in Figure 4. So long as knob 23 is in the position shown in Figure 3 the brakes can be released or applied to the full extent or any partial extent desired, e. g. while landing. When the aeroplane has been brought to rest and it is desired to leave the brakes fully applied for parking, the knob 23 is moved over to the position shown in Figure 4 so that the detent 24 lies across the path of screw I7. On releasing the brake lever l the brakes will be maintained fully applied, since screw ll will abut against the detent 24. If desired a lug may be provided projecting inwards from the upper part of bearing 2 I, as seen in Figure 3, to limit the upward movement of screw I! and thus the maximum extent of application of the brakes.

Having described my invention, what I claim is: 1. Apparatus for actuating a cable which comprises a fixed supporting plate having a slot and a cam surface, a hand actuated lever bifurcated to straddle said plate, said lever having a cam follower mounted between the bifurcated part of said lever to engage said cam and a roller mounted between said bifurcated part of said lever to engage said slot and an adjustable stop on said lever and a rotatable detent mounted relative to said plate to move into and out of position to engage said adjustable stop.

2. Apparatus for actuating a cable which com prisesa fixed support having a guide plate, said guide plate having a guide slot and a cam surface, a hand operated lever having a cam follower engaging said cam surface and a roller engaging said slot, a threaded adjustable stop mounted on and movable with said lever and a knob rotatably mounted on said support and having a projecting detent, said detent being positioned in one position of rotation of said knob to one side of said stop and in another position of said knob in the path of said stop.

3. Apparatus for actuating a cable which comprises a supporting and guiding plate having a slot and a cam surface, a hand lever being a cam follower engaging said cam surface and a roller engaging said slot, a lug projecting from one face of said lever, a set screw mounted in said lug with its axis parallel to said slot, a detent movably mounted relative to said plate and movable from a position clear of said screw to a position to stop said screw.

HENRY WILLIAM TREVASKIS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 634,493 Bradley Oct. 10, 1899 656,140 Kennedy Aug 14, 1900 FOREIGN PATENTS Number Country Date 186,124 Switzerland Nov. 16, 1936 190,766 Great Britain Jan. 2, 1923 345,449 France Nov. 30, 1904 

